products. The Soxhlet extraction set up consists of a
heating plate, conical flasks, a Soxhlet extractor, and a
condenser. The heating plate was used to vaporise the
solvent (n-hexane) contained in the conical flasks. The
condenser was used to condense the solvent (hexane)
vapour.
The solvent was first vaporised and the vapour was
allowed to by-pass the Soxhlet extractor and to enter
into the condenser. The condensed solvent was collected
around the thimble. The thimble contained the crushed
meat samples. Extraction took place during the time
when the solvent condensate was allowed to pass
through the crushed meat. When the liquid level reached
to the top of capillary tube, the solvent with the extracted
fat from meat, was drawn back into the conical
flask. The extraction continued when the solvent was
once again vaporised and condensed in the thimble.
Meat samples underwent drying and crushing prior
to oil extraction. The extraction period was found to be
4 h, based on trial and error. A series of repetitive experiments
were carried out in order to evaluate the
characteristics of meat patties cooked by the two
methods. The moisture and oil content of meat patties
cooked by both cooking methods are shown in Table 2.
From the experiments, it was concluded that the meat
quality was not altered significantly by applying ohmic
heating, which is evident from the values of the moisture
and fat contents reported in Table 2.
5. Conclusions
The application of combined ohmic and plate cooking
of hamburger patties was found very successful in
reducing cooking time and producing safer products.
Quality measurements of the meat patties cooked by the
newly developed method and the conventional method
showed similar moisture and fat contents. Mechanical
properties of the two products were also similar.